KR20070103438A - Sealing film dressing - Google Patents

Abstract

The present invention relates to a film dressing comprising a thin plastic film (2) coated with an adhesive (3). In accordance with the invention, the adhesive (3) has a softness of 10-22 mm, and the adhesive coating has a weight per unit area of 50 g/m^2 or more.

Description

Sealing film dressing {SEALING FILM DRESSING}

The present invention relates to a film dressing comprising a thin plastic film coated with an adhesive.

In the early 1980s, a new type of wound dressing was introduced by Smith & Nephew, a company that manufactures wound dressing products. This product, still on the market and sold under the trade name OpSite ™, is based on the invention described in British patent GB 1280631. The dressing also consists of a very thin polyurethane film of about 25 micrometers coated with a thin self-adhesive adhesive layer of about 25 micrometers. Since it is thin, the film is very flexible and supple. It can be firmly attached and can be relatively tightly sealed around the wound on the convex, concave, unsmooth skin surface. However, any wrinkles that form may sometimes create thin channels that can leak fluid. This dressing was completely different from all previous dressing products, forming an entirely new class known as self-adhesive film dressings. More companies have produced similar products, and many film products with similar functions and characteristics are available on the market today. These film dressings were soon found to be important for the fixation and protection of intravenous cannulae (eg Venflon cannula form). They are also used to cover other types of wounds, such as areas where the skin has been removed in connection with skin grafts.

Contrary to the above mentioned characteristics, an important factor for the successful sale of film products has been the successful development of an effective application system. Thin dressings were very difficult to handle without a specially designed application system. Thus, for this purpose, a harder carrier material is usually attached to the non-adhesive coated side of the film in a removable manner to impart rigidity to the product (otherwise easily entangled in connection with attachment to the skin). The carrier material that imparts rigidity to the thin film is not removed from the product until the self-adhesive film is applied in the intended place.

Film dressings have been improved in various ways more recently. Specially designed intravenous fixation films have been developed to have a narrow slot perforated to leave space for tube connection of the intravenous cannula and in doing so to improve its function. Many film dressings have wound pads (so-called island dressings) covering the center of the adhesive-coated side and allow some absorption of liquid from the wound to be achieved when the film dressing is covered on the wound.

The above-mentioned dressing class, self-adhesive film dressings, nevertheless has been found to have many of its own vulnerabilities:

1. A relatively aggressive adhesive was used to achieve firm fixation without risk of loosening the film dressing. The manufacturer chose an aggressive form of adhesive to satisfy itself so that the dressing already adhered to the skin sufficiently firmly after application. The reason is to avoid accidental loosening of the intravenous cannula, which is a risk to the safety of the patient. It is also desirable to avoid wound fluid from penetrating the adhesive joint between the film and the skin, flowing out of the wound and leaking to healthy skin outside the dressing. The type of adhesive used today is characterized by a substantial increase in adhesion to the skin over time. The adhesion strength of many film dressings increases several times over 2-3 hours or 2-3 days compared to the adhesion immediately after application. When attaching film dressings too strongly they often cause redness and pain when removed from the skin. They also detach epithelial cells from the skin and impair the barrier function of the skin. Nevertheless, manufacturers choose these types of adhesives because it is paramount that they adhere well enough immediately after application.

2. In investigating the protection against leakage from film dressings, we have identified unexpected weaknesses in ordinary film dressings. Studies under the microscope showed that, despite the fact that the film dressing was completely tightly sealed and firmly attached to the skin, the liquid could easily spread under the film dressing. It has been found that fluid can spread several centimeters under the dressing through the microscopic folds of spontaneous generation in normal skin. This has previously been ignored because the leak consists of very small amounts and is not visible when examining the internal leak of the colorless liquid. A phenomenon known as micro-leakage was first observed when the solution was stained with a strongly colored pigment. The transport of fluid under the film dressing can be a major risk to the patient because microorganisms can be transported from the skin under the dressing or out of the skin to the wound. Infections from the central venous catheter ((CVC) will often be covered with a film dressing, which can be a risk to the patient's life.Manufacturers of film dressings often sell these as "shower proof". When showering, the risk of micro-leakage of the type described above naturally increases significantly.

3. Adhesives for film dressings sold today show high adhesion to hair. Since these dressings are often applied to the hairy skin surface, pain and hair pulling often occur when the dressing is removed.

It is an object of the present invention to solve the above-mentioned problems while retaining all the advantages provided by thin elastic carrier materials such as softness and slippage which are the unique strong features of the film dressing product form.

This object is achieved by a film dressing comprising a thin plastic film coated with an adhesive, wherein the adhesive has a softness of 10-22 mm and the adhesive coating has a weight per unit area of at least 50 g / m 2. Microscopic leakage is prevented by the fact that the adhesive coating has a high weight per unit area and the adhesive has a high degree of flexibility. The flexible adhesive also shows the correct level of adhesion immediately after application, and the adhesion does not increase at all or only slightly increases with time. The attachment to the hair is also very low so that the hair hardly remains in place.

In a preferred exemplary embodiment, the adhesive consists of a silicone elastomer, or alternatively a hot-melt adhesive.

The film dressing is also leak proof according to the MHC leak test with a groove depth of 75 micrometers.

The thickness of the plastic film is less than 50 micrometers. The plastic film preferably has a thickness of 12-25 micrometers and flexural rigidity of less than 3 mm and preferably less than 1.8 mm.

The adhesion strength to the steel of the attached dressing preferably does not vary by more than 5% over a period of 1 minute to 48 hours.

The invention is now described below with reference to the accompanying drawings.

1 schematically illustrates a cross section through a film dressing according to a preferred embodiment of the invention.

2 schematically illustrates the measurement of adhesion strength to the skin.

3 shows the cone used for the softness measurement.

4 illustrates a measurement method for measuring flexibility.

5-11 illustrate MHC leak tests.

12-14 illustrate a method of measuring the bending stiffness of a plastic film.

15-17 illustrate a method of measuring adhesion to steel.

18 shows the results of the MHC leak test.

19 shows the adhesive strength as a function of time for many dressings.

The way of carrying out the invention

1 illustrates a cross-sectional view of a film dressing 1 according to a preferred embodiment of the present invention. The dressing consists of a thin plastic film layer 2, preferably made of polyurethane plastic, coated with a layer 3 of flexible skin-friendly adhesive. The thickness of the plastic film is preferably between 12 and 25 micrometers and in any case less than 50 micrometers. The weight per unit area of adhesive layer is equal to or greater than 50 g / m 2.

The plastic film has a flexural rigidity of less than 3 mm and preferably less than 1.8 mm using the method described below.

The carrier layer 4 is also applied on the film layer 2, ie on the side facing away from the adhesive layer 3 to facilitate the application of the film dressing. The function of the carrier layer is to stiffen the film dressing comprising the adhesive coated thin plastic film, the carrier layer may for example consist of polyethylene film or polyethylene-coated paper, the polyethylene layer facing towards the film It has a thickness of 50-300 micrometers. The adhesive layer 3 is protected in a conventional manner by protective layers 5, 6 of a material having low adhesion to an adhesive, for example polyethylene-coated paper or polyethylene film.

The carrier layer 4 is preferably coextruded with the film, or the film may be formed in the carrier layer.

In connection with the application of the film dressings 2, 3, the protective layer 5 is first removed and then the dressing is placed on the skin of the user. The protective layer 6 is then removed and a portion of the dressing attached to the layer 6 is firmly pressed onto the skin. Finally, the carrier layer 4 is removed.

The bending stiffness of the plastic film is determined in the manner described below. Front and side views, respectively, as shown in Figs. 12 and 13, a test piece FS having a size of 15 x 120 mm spans the edge of a 0.3 mm thick metal sheet. The end of the test piece FS is reinforced with copy paper having a double-sided adhesive tape pieces R and a size of 15 x 40 mm (weight = 0.13 g); See FIG. 14. It is important to ensure that the sample spans the metal sheet so that the sample spans the same amount on both sides of the metal sheet. After 30 seconds, photographs of the overlaid samples are taken with a digital camera as shown in FIG. 12. Position the scaled ruler appropriately for inclusion in the picture. The bending stiffness was then obtained from the photograph taken by measuring the distance between the ends of the sample at a point 5 mm below the top of the sample. The greater the distance between sample ends, the higher the bending stiffness exhibited by the sample FS. In order for the plastic film along with the flexible adhesive to be able to conform to all uneven areas in the skin, the flexural rigidity of the film should be less than 3 mm and preferably less than 1.8 mm.

The main function of the adhesive coating (3) is to tightly attach the film dressing (1) to the patient's skin to prevent the transport of liquid-mediated bacteria between the skin and the adhesive coating, and to firmly adhere the film dressing to the skin This is to ensure that the product remains in place while the dressing is subjected to all normal loads it receives.

The adhesive in the coating should also be skin friendly and should allow removal of the film dressing without causing damage to the skin. This requirement presents a major problem in the case of these forms of pressure-sensitive adhesives currently used as adhesive coatings for film dressings. Such adhesives often adhere strongly to the skin itself, causing portions of the stratum corneum, ie, the top layer of skin, to stick to the adhesive and to be pulled away from the skin when breaking the adhesion of the film dressing. This is particularly true for patients with sensitive skin, for example, patients aged 70 years or older, children under 3 years old, patients with certain diseases such as asthma, or patients undergoing constant treatment such as cortisone treatment. May irritate and damage the skin.

Silicone elastomers are very flexible and have low surface energy and are very well suited for the skin. In other words, it flows into any uneven portion of the skin and creates a large contact surface between the skin and the silicone elastomer. This large contact surface helps firmly adhere to the skin despite the fact that the strength of the adhesive adhesion of the silicone elastomer to the skin is not so strong in itself. Adhesive strength constitutes a measure of the energy required to separate and pull off the adhesive layer from the skin. The cause of the fact that high energy, and therefore high pulling force, is required to remove the silicone elastomer from the skin, is due to the fact that despite the relatively weak strength of the adhesive adhesion, a lot of energy is required to stretch the flexible silicone elastomer before detaching it from the skin. It is consumed. The softer and thicker the layer of silicone elastomer, the greater the force / energy required to remove the elastomer from the skin.

The use of harder adhesives will require a stronger adhesive bond strength in order for the pulling force to be as high as for a more flexible adhesive. Strong adhesive attachment between the skin and the adhesive can easily pull skin cells away from the skin in conjunction with removal of the adhesive.

Another disadvantage associated with harder adhesives is that they can ultimately flow out and thus increase the size of the contact surface with the skin as a result of the ultimate increase in pulling force, which makes it difficult for these adhesives to eventually remove from the skin. It can be difficult. Unlike harder adhesives, more flexible adhesives, such as silicone elastomers, all achieve sufficient adhesive strength at one time so that their pulling forces remain constant over time.

Because the properties of the skin vary from person to person, the adhesive ability of the adhesive coating to the skin naturally also varies for other patients. Adhesive strength also depends on the thickness of the flexible adhesive and the mechanical properties of the barrier layer. Standard methods for the measurement of adhesives available today use various kinds of plates, for example those made of steel or glass, which do not give relevant values for the measurement of adhesion to the skin. Values for the strength of adhesive adhesion to the skin of the adhesive should be measured by a method of the type schematically illustrated in FIG. 2 developed by the applicant, as indicated below.

A strip of self-adhesive film dressing to measure the strength of adhesive adhesion to the skin is stamped in a size of 25 x 125 mm. It should be noted that all strips have a carrier layer on the back of the film dressing. (The function of this carrier layer is to stiffen the strips as they are applied to the skin.) The strips are then applied to the skin on the back of healthy volunteers. Carefully tuck the strip into place with your fingers and remove the carrier layer on the back of the strip. Finally, the strip is firmly pressed against the skin for 3 seconds with the help of a sponge made of foamed plastic (42 x 182 mm, thickness = 48 mm) firmly bonded to the steel sheet (50 x 200 mm, thickness = 1 mm). . The pressure applied is estimated to be 6 kN / m 2. Leave the strip in place for 2 minutes. The strip is then pulled off at a rate of 25 mm / sec and the removal force F1 is measured. The clearance angle, ie the obtuse angle formed between the surface of the skin and the removed part of the strip, should be 135 °. The strength of adhesive adhesion of the strip to the skin consists of the average value of the forces F1.

Adhesives suitable for use in the film dressings according to the invention should exhibit a strength of adhesive attachment of at least 0.2-3 N / 25 mm according to this method. The strength of the adhesive attachment is preferably 1-2.5 N / 25 mm.

The adhesives according to the invention should exhibit a softness exceeding 10 mm measured by methods based on ASTM D 937 and ASTM D 51580. As can be appreciated below, certain modifications have been made. 3 and 4 show a test piece (C) of 30 mm thickness of the adhesive to determine the softness of the adhesive, which measures the softness of the adhesive by causing a cone (B) having a weight of 62.5 g under the influence of gravity to cause penetration. A modified method is illustrated. The test specimen is obtained by filling the adhesive with a depth of 30 mm in a cylindrical glass container with an inner diameter of 60 mm and an inner height of 35-40 mm. In the case of silicone elastomers, it is necessary to fill the vessel with an uncured silicone prepolymer and then crosslink it to the elastomer in a glass cylinder. The cone used is illustrated in FIG. 3 and has the following sizes: a = 65 mm, b = 30 mm, c = 15 mm, and d = 8.5 mm. In carrying out the method for the measurement of softness, cone B first descends to position I as illustrated by the dashed line in FIG. 4 where the tip of the cone is in direct contact with the surface of test piece C. The cone (B) is then placed so that it can penetrate the specimen (C) under the influence of gravity. After 5 seconds the tip of the cone (B) has penetrated the specimen (C) and has a penetration value (P), which is larger in proportion to the softness of the specimen. Penetration value (P) represents the softness index used in the present invention. A PNR 10 hardness meter supplied by Sommer & Runge KG (Germany) is used in the method of the invention.

In the case of a flexible skin-friendly adhesive that forms a barrier that prevents the liquid from flowing through, it is also possible that the liquid may leak through these barriers through cracks in the skin, folds in the skin, or uneven portions in other skins. Found. This leak can cause germs to spread, which in turn can lead to wound infections.

Surprisingly, for skin-friendly adhesives, it has been found that the above leakage risk can be eliminated or at least significantly reduced if the adhesive is sufficiently flexible and has a weight high enough per unit area.

The method described below, also known as the MHC leak test, was developed by the applicant for the purpose of determining whether the film dressing is leak proof. A specimen S having a size of 30 × 30 mm and a circular hole (d = 12 mm) in the center of the sample was punctured from the dressing to be tested. Colored test solutions are prepared by mixing 0.2% by weight of Patentblatt V (VWR International, Sweden) and 0.1% by weight of Teepol Gold (Teepol Products, UK) with deionized water. An aluminum test plate T having a size of 15 x 50 x 50 mm and having 15 milled grooves; See FIG. 5 showing the top view of the plate and FIG. 6 showing the side view of the plate. For a more detailed description of the shape of the grooves see FIG. 7 showing a cross section through a portion of the plate.

In Fig. 7, the depth of the groove is 75 micrometers, but if you want to test for protection against leakage of gold or folds of the skin at other groove depths, for example 50 micrometers or 150 micrometers, Depth can also be used.

The specimen S is then carefully centered over the grooves of the test plate T so that no bubbles occur between the test plate and the specimen; See FIG. 8. When the sample is placed on the plate the pressure may not reach the sample, so if bubbles occur, they should not be pushed with the aid of fingers, but the sample should be lifted and repositioned or otherwise rubbed.

Next, a piece of polyurethane foam (L00562-6, 1.6 mm Rynel, Inc., Boothbay, ME, USA) having a size of 50 x 50 mm is placed on the sample (S) and the test piece (T). Then, a mangle (roller) made of metal (44 mm wide, r = 48 mm, weight = 995 g) is rolled on the foam and the specimen at a speed of 5 mm / sec; See FIG. 9. Roll the mangle back and forth over the sample.

A piece of foam is removed from the sample (S) and 65 μl of test liquid is put into the hole of the sample with the help of a pipette. The test liquid is evenly distributed in the hole with the aid of the pipette tip, so that the liquid reaches all points of the edge of the sample. Start the stopwatch as soon as all the test liquid is evenly distributed in the hole. After 30 minutes, the photograph of the specimen (S) was taken with a digital camera and the test piece (T) was placed on a test plate with a graduated ruler.

Measure the following distance using the photograph. For all the grooves in contact with the hole of the sample, i.e., the distance d from the edge after the hole to the edge at the end of the sample in all the grooves where liquid is expected to penetrate; See FIG. 10 indicating this distance d1 for one of the grooves. Then add all these distances d together and they become the total distance that the sample can leak. Thereafter, measure the distance e at which the test liquid leaked from all the grooves of the plate; See FIG. 11 showing the distance e1 for one of the grooves. The sum of all distances e indicates the total leak distance.

Finally, leaks are obtained by dividing the sum of the leak distances (e) by the total distance (d) at which the sample can leak. This index is then converted to a percentage number by multiplying it by 100. The evaluation of the sealing is carried out as follows. A result> 10% leak was considered a leak. A leak of 10% of the results was considered a sealing.

Between each measurement performed on the test plate, the plate shall be cleaned in the following manner. The plate is first rinsed with water and then washed with n-heptane. Ensure that no adhesive residues remain in the grooves on the plate, and that nonwoven compressed flexible materials (Mesoft®, Molnlycke Health Care) can be immersed in n-heptane and used to rub the adhesive residue in the grooves of the plate It is important to do. Finally, the plates should be allowed to dry in the air before being reused.

Other solvents may be used for the adhesive that is not soluble in n-heptane.

The reason for studying for a while after application of the test piece is that some leakage occurs due to capillary action, which may make it difficult to determine whether the test piece is leak-proof immediately after application.

The test method described above with a groove depth of 75 micrometers in the groove of the aluminum plate, with 25 +/- 5 with an adhesive coating of skin-friendly adhesive having a softness of about 20 mm and a weight per unit area of about 50 g / m 2. Test pieces comprising a transparent polyethylene film with a thickness of micrometers have been proven to be leak proof according to this test. Test pieces with such an adhesive coating have also been found to be leak-proof in normal smooth skin of young and middle-aged people. Thus, it may be necessary to use a weight per unit area of at least 50 g / m 2 to ensure resistance to leakage in the area of wrinkled skin.

The effect of leakage resistance on the weight and softness of the adhesive per unit area in the adhesive coating was investigated by this method with respect to the silicone elastomer Silgel 612 (manufactured by Wacker Chemie GmbH, Germany).

According to the MHC leak test with a groove depth of 75 micrometers, the leak was measured for many different film dressings with different softness values for the adhesive and different weight per unit area. All dressings were made by coating a polyurethane film having a thickness of 25 ± 5 with Silgel 612 with different softness values and different weight per unit area. The results are shown in FIG.

The results clearly show a link between the softness (penetration) of the silicone elastomer and the weight per unit area. The softer the silicone elastomer, the smaller the weight per unit area required for the seal. The results indicate that for a sufficient number of measurements it is possible to create a curve that accurately indicates the minimum weight per unit area required at a given softness to ensure a seal on the skin. The results make it clear that this curve is initially horizontal, ie with a steep slope in the case of less flexible adhesives and then horizontal. Thus, the relationship between weight per unit area and softness requires very flexible adhesives to achieve sealing at low weight per unit area, while less flexible adhesives require higher weight per unit area to achieve sealing. It is clear that achieving fluid-tight films at softness values of less than 10 mm is difficult and possibly even impossible. At softness values on the order of 20 mm, a weight per unit area of 50 g / m 2 is sufficient to achieve sealing.

It should be added that all known film dressings tested were found to leak.

As can be appreciated from FIG. 18, some points are consistent because many tested film dressings have approximately the same weight and softness values per unit area.

Apart from increasing the leak resistance, a higher weight per unit area for the adhesive coating is associated with a reduced risk of blisters, rashes or other damage occurring on the skin at the edge of the applied adhesive. This damage can occur in conjunction with movement in the film dressing carrier resulting in relative movement between the skin and the adhesive coating, or as a result of the dressing being subjected to external loads, for example due to an object tapping the film dressing carrier. . The risk of occurrence of such damage was found to be reduced to higher weight per unit area and higher flexibility for the adhesive coating. This is due to the fact that the presumed proportion of the load is absorbed by the adsorbent layer through deformation and not transferred to the skin in this way. The film dressing according to the invention can also stretch together with the skin, which reduces the risk of shearing between the adhesive and the skin which can cause mechanical damage to the skin.

It is recommended that the softness of the flexible skin-friendly adhesive used to ensure that only a low application force is required in connection with the application of the film dressing according to the invention should be greater than 10 mm, preferably between 12 and 17 mm. . The softer the adhesive, the faster it will flow into any uneven portion of the substrate, which means that the film dressing according to the invention is leak-proof immediately after application to normal skin. At softness values greater than 17 mm, the internal adhesion of the adhesive is too low, and there is a risk that the residue of the adhesive remains on the skin in connection with the removal of the applied film dressing.

Another important characteristic of the film dressings according to the invention is that the strength of the adhesive adhesion of the flexible skin friendly adhesives used in these dressings does not change over time or only changes to a slight extent over time. This has been demonstrated by measuring the adhesive adhesion strength to the skin for the film dressing according to the invention containing silicone elastomer as a number of known film dressings and adhesives. Known film dressings include Tegaderm ™ (3M Health Care, USA); OpSite ™ IV3000 ™ And OpSite ™ Flexigrid ™ (manufactured by Smith & Nephew Medical Limited, UK). The measurement was carried out by the above method for the measurement of the strength of adhesive adhesion to the skin, with the difference being 1 minute, 10 minutes and 3 hours later. The results are shown in FIG. 19. As can be appreciated from this figure, the strength of the adhesive adherence increased steeply with time for known film dressings, while the dressing according to the present invention showed in principle unchanged adhesion. Numerically, the adhesive adhesion strength from 1 minute to 3 hours increased to 295% for OpSite ™ Flexigrid ™, 209% for Tegaderm ™ and 318% for OpSite ™ IV3000 ™.

The strength of adhesive adhesion to the steel for the corresponding dressing and the Mefilm® dressing from Molnlycke Health Care AB (Sweden) was also measured by the method described below.

Specimens having a size of 25 × 120 mm were punctured from the test material. A piece of paper having a size of 25 x 250 mm is punched out of the copy paper. The steel plate (according to ASTM A 666-94 A, 50 × 200 mm) is washed with lint-free absorbent material saturated in n-heptane and washed three times with this solvent. Finally, a final wash is performed with acetone in place of n-heptane. The steel sheet is then allowed to dry for at least 10 minutes but not longer than 10 hours. A piece of paper is attached to the sample at one end against the adhesive and the piece of paper is fixed in place using a stapler. An important consideration is to ensure that the paper is firmly attached to the specimen so that it cannot slip off in conjunction with the application of the load. The overlap between the specimen and the piece of paper shall be 10-15 mm; See FIG. 15 (side view). The specimen is then placed on a clean steel sheet with the adhesive facing the steel sheet. It is important to lay the specimen carefully on the grater to avoid pressure on the specimen. A piece of polyurethane foam (L00562-6, 1.6 mm Rynel, Inc., Boothbay, ME, USA) was then placed on the sample on the test plate and the mangle (roller) on the piece of foam (1) at a rate of 5 mm / sec. (45 mm width, weight = 445 g, r = 47 mm) is attached to the plate by rolling back and forth once; See FIG. 16 (side view). The specimens are tested one minute or one hour after rolling in mangles.

The test is carried out as follows. Secure the steel sheet to the lower clamp of the tensile tester (Instron 4301, Instron 4464 or equivalent) so that the piece of paper is suspended vertically down. Then fold the piece of paper up 180 degrees and fix it firmly to the upper clamp of the tensile tester; See FIG. 17 (side view). Start the tensile tester and record the average force required to pull the specimen from the steel sheet. Tensile testing machines should be operated at a speed of 300 mm / min.

Average forces for the other film dressings were measured after 1 minute and after 1 hour. The adhesive bond strength increased after 1 hour by 22% for Tegaderm ™, 58% for Mefilm®, 37% for OpSite ™ IV3000 ™, and 27% for OpSite ™ Flexigrid ™, while No increase in strength of adhesive adhesion was measured for the film dressing.

Furthermore, hair is not pulled out when removing the film dressing with the flexible skin friendly adhesive.

The product proposed in the present invention is usually supplied sterilely packed, which means that the adhesive used must be sterile and that other components of this article can of course also be sterilized.

The described embodiments of the invention can naturally be modified within the scope of the invention. Forms of a carrier layer other than the plastic layer described herein may be used, for example a carrier layer made of paper. It is also possible to apply an absorbent to the dressing to produce so-called island dressings. It is also conceivable to apply other materials to the adhesive, such as ZnO, skin protectors, or antimicrobial agents, which are placed so that they slowly leak out of the skin. It is also possible to supply the hydrophilic particles or the like to the adhesive. Moreover, the film may puncture one or more holes, or may form a slot. The invention should therefore be limited only by the content of the following claims.

Claims (9)

A film comprising a thin plastic film 2 coated with an adhesive 3, characterized in that the adhesive 3 has a softness of 10-22 mm and the adhesive coating has a weight per unit area of at least 50 g / m 2. Dressing (1). 2. Film dressing according to claim 1, characterized in that the adhesive (3) consists of silicone elastomer. 2. Film dressing according to claim 1, characterized in that the adhesive (3) consists of a hot-melt adhesive. 4. Film dressing according to claim 1, 2 or 3, wherein the film dressing (1) is leak proof according to the MHC leak test with a groove depth of 75 micrometers. The film dressing as claimed in claim 1, wherein the thickness of the plastic film is less than 50 micrometers. 6. The film dressing of claim 5, wherein the plastic film has a thickness of 12-25 micrometers. 7. Film dressing according to claim 5 or 6, characterized in that the plastic film has a bending stiffness of less than 3 mm and preferably less than 1.8 mm. 8. Film dressing according to any one of the preceding claims, characterized in that the adhesive strength of the adhered dressing (1) to the steel does not vary by more than 5% over a period of 1 minute to 48 hours. The film dressing according to any one of claims 1 to 8, wherein a substance such as ZnO, a skin protective substance or an antimicrobial substance is added to the adhesive.

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